Gas burner



R. A. ELMY GAS BURNER Dec. 6, 1966 Filed Jan. 9, 1964 Fig.5.

United States Patent Gfiiice 3,239,73fl Patented Dec. 6, 1966 3,289,730 GAS BURNER Richard A. Elmy, Mansfield, Ohio, assignor to Westinghouse Electric Corporation, East Pittsburgh, Pin, a corporation of Pennsylvania Filed Jan. 9, 1964, Ser. No. 336,705 4 Claims. (Cl. 158-113) This invention relates to gas burners, and more particularly to a gas burner for use in clothes dryer apparatus.

In the application of a gas burner to a clothes dryer, it is customary to provide a burner which produces a relatively flat frame for heating purposes. To accomplish this result, a flame spreader device is generally employed adjacent the outlet port of the gas burner. While the general purpose of a flame spreader is to hold the flame to the nozzle port, preventing lifting or pulling of the flame from the port, various changes in shape may be made to produce a long, short, flat, round, or curved type of flame, depending on the application.

One of the problems prevalent in the design of gas burners of the type described, is the burning out of the spreader device during the life of the clothes dryer equipment. In order to effectively spread the flame from the nozzle port, a flame spreader is generally introduced into that portion of the flame adjacent the nozzle port resulting in extremely high temperatures on the metal flame spreader surfaces. These high temperatures often exceed the allowable temperature of the spreader, resulting in burn spots.

In addition to the problem of flame spreader burning produced by high temperatures, most burner structures heretofore employed in clothes dryer applications have comprised a plurality of sheet metal parts welded to a tubular element. Such structures require the purchasing, storing and fabrication of a great number of parts, in addition to the complex assembly of the burner employing a number of fixtures and welding operations.

It is therefore, an object of the present invention to provide a gas burner having a flame spreader which is cooler in operation than flame spreaders employed in gas burners heretofore.

Another object of the invention is to provide a gas burner which is simple in construction and inexpensive to manufacture.

A further object of the invention is to provide a gas burner which is easily fabricated by a stamping process employing a single pair of dies.

These objects of the invention, and other objects which will become apparent as the description proceeds, are achieved by providing a novel gas burner wherein the flame and unburned gases emanating from the nozzle are provided a smooth flow path over the flame spreader surfaces. The structural arrangement thus provided is simply manufactured in corresponding half segments having flanges provided for ease of assembly.

In addition, the novel method of manufacturing produces a structure to which a simple air shutter arrangement is easily applied.

- For abetter understanding of the invention reference should be had to the accompanying drawings, wherein:

FIGURE 1 is an exploded perspective view showing one embodiment of the invention;

FIG. 2 is a top plan view showing the gas humor of FIG. 1 in operation;

FIG. 3 is a side elevational view of the gas burner of FIGS. 1 and 2 showing the burner in operation;

FIG. 4 is a sectional view taken along line IVIV of FIG. 2, showing details of the invention on an enlarged scale for clarity; and

FIG. 5 is a sectional view taken along line VV of FIG. 2, showing details of the invention on an enlarged scale, as in FIG. 4, for clarity.

Although the principles of the invention are broadly applicable to atmospheric burners in general, the invention has been herein illustrated as employed in a gas burner for a domestic clothes dryer and will be so described.

Referring to the figures, especially FIGS. 1 and 2, there is shown a gas burner Jltl having a pair of elements 11 and 12 comprising half segments of the main body portion of the burner. Each of the elements 11 and 12 has a semi-cylindrical portion 13 and M respectively and a relatively long tapered groove 16 and 17 respectively of semi-circular cross section. The semi-cylindrica1 portions 13 and 14 each have a semi-circular opening 18 and I9 respectivelyprovided at one end, and a small radius end 21 and 22 respectively of the groove 16 and 17 opening into the opposite end of the portion. The opposite, larger radius, end of each of the grooves 16 or E7 is further provided with an inwardly extending radial portion 23 and 24 respectively.

The element it differs from the element 12 in that it is provided with a hemispherical bowl 26 extending axially from the groove 17 and having its rim or peripheral edge 27 engaged at the inwardly extending radial portion 24. Each of the elements 11 and 12 are provided with a pair of outstanding flanges which are designated by the numerals 2'7 and 28 respectively.

Referring now to the FIGS. 2 through 5, it will be seen that the elements 111 and 12 are assembled by placing the flanges 27 and in facing relation, and fixing the flanges by any convenient means such as spot welding. By so fabricating the elements 1}. and 12, the semi-cylindrical portions i3 and id form the burner mixing chamber and the tapered grooves 16 and 17 provide a venturi for the gas burner. The mixing cham er is provided with a pair of openings 31 and 32 for entry of primary air, and the cooperating semi-circular openings 18 and I provide a circular opening for entry of gas from a conduit 33 inserted into said opening.

A slidable air shutter comprising a pair of semi-circular cover members 34 and 35 is disposed around the mixing chamber. Each of the members 3d and 35 has a pair of outstanding flanges 3t) and fail corresponding to the flanges 27 and 28 and a pair of gripping flanges 44 and 45 respectively. Slotted openings 36 and 37 are provided in the flanges 27 and 23, and the cover members 34 and 35' are attached through the slotted openings by a pair of nut and bolt assemblies 33 and 39. When attached as shown in FIGS. 2 through 5, the cover members are slidable by grasping the flanges 4d and 45 and causing the valve to move along the flanges Z7 and 28 to adjust the primary air to the mixing chamber.

In operation, the combustible gas, which may be natural, mixed, manufactured or liquid petroleum air gases, is provided through the conduit 33 and enters the mixing chamber. In the mixing chamber, the gas is mixed with air which enters through the openings 31 and 32. The mixture passes through the burner throat formed by the mating small radius opening 21 and 22 The gas and air mixture flows through the venturi formed by grooves 17 and 18 and then passes through the nozzle port formed by the inwardly extending radial portions 23 and 24. The nozzle port formed by the radial portions 23 and 24 is located adjacent the hemispherical bowl 26 in a position whereby all the gas and air mixture flows into the hemispherical bowl and is spread into a thin sheet of flame as shown in FIGS. 2 and 3. It will be noted that the peripheral edge of the bowl 26 is constructed to introduce a radius portion 41 into the flame to produce the flame structure shown.

By tracing the flow of gas through the burner, it will be seen that the gas mixture passing through the venturi and over the spreader provided by the bowl 26 at no time impinges on a sharp metal corner or edge, but that a smooth flow path is provided for the flow of burning gases from the nozzle and over the flame spreader.

By providing a flame spreader structure presenting only radial surfaces to the flame, a cooler operating flame spreader than heretofore known has beenproduced. In addition, the location of the nozzle port adjacent the flame spreader provides for flow of substantially all the gas into the spreader. This flow of burning gases mixed with the unburned gases passing over the peripheral edge of the bowl 26 tends to cool the edges and eliminates burned spots on the spreader.

From the foregoing it should be evident that the in vention provides a cooler operating gas burner which tends to retain its clean appearance after an extended period of use and may, therefore, be finished in silicon aluminum paint, porcelain enamel, or stainless steel.

While the invention has been shown in but one form it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

What is claimed is:

1. A gas burner structure comprising means defining a chamber for mixing gas and air,

a venturi tube having one end opening into said mixing chamber,

a flame spreader disposed at the opposite end of said tube,

said flame spreader comprising a hemispherical bowl having,

a radiused flange disposed at the peripheral edge thereof and merging smoothly with said opposite end of said tube,

whereby gas flowing from said venturi tube is provided a smooth flow path over said peripheral edge of said flame spreader bowl.

2. A gas burner structure comprising means defining a cylindrical chamber for mixing gas and air,

a venturi tube having an opening at one end connecting with said chamber and a larger opening at the opposite end thereof,

said larger opening having an inwardly extending annular flange defining an outlet port for flow of gas from said venturi tube,

a flame spreader having a hemispherical bowl,

an outwardly extending flange disposed adjacent the periphery of said bowl,

the intersection of said bowl and said last-mentioned flange merging in a smooth radius extending over the greater portion of said bowl periphery,

said flame spreader being disposed tangentially to and extending outwardly from said outlet port with its flange merging smoothly with the flange defining the venturi tube outlet port to provide for the smooth flow of gas from said burner,

3. A gas burner comprising,

a pair of elements each having a semi-cylindrical portion with a pair of end walls,

a relatively long tapered groove of semi-circular cross section having a small radius end connecting with an end wall of said semi-cylindrical portion and opening into said portion,

said groove having a larger radius end provided with an inwardly extending radial portion, and

a pair of co-planar flanges each extending from a side of said semi-cylindrical portion and said tapered groove, one of said elements further having a hemispherical bowl extending axially from said large radius end of said groove and having its rim engaged with said groove at said inwardly extending radial portion,

said bowl being provided at the periphery thereof with an outwardly-projecting flange radiused in cross section and converging into said inwardly extending radial portion at the intersection of said bowl and said tapered groove,

said elements being disposed in facing relation with said tapered grooves axially aligned and said flanges abutting and joined together,

whereby said semi-cylindrical portions define a mixing chamber of said burner, said tapered grooves define a venturi section of said burner, said inwardly extending radial portion defines an outlet port and said hemispherical bowl provides a spreader for producing a relatively flat sheet of flame emanating from said nozzle.

4. The structure of claim 3 wherein said semi-cylindrical portion of each of said elements has an opening provided therein for entry of air to said mixing chamber, and

a slidable air shutter member for adjusting the quantity of air entering said chamber,

said valve comprising a pair of semi-circular cover members each having a pair of co-planar radially outwardly extending flanges, said cover members being disposed in facing relation, with said outwardly extending flanges in contact with said flanges of said semi-cylindrical portions, and

fastening means for holding said cover members in diametrically opposed relation and slidably mounting said cover member flanges adjacent said flanges of said semi-cylindrical portion,

whereby said cover members are movable from a position covering said openings to a position partially covering said openings for adjusting the quantity of air entering said mixing chamber.

References Cited by the Examiner UNITED STATES PATENTS 1,095,795 5/1914 Brand 158--113 1,519,010 12/1924 Raznor 29157 1,842,395 1/1932 Farrington 158118 X 2,565,039 8/1951 Mueller 158-7 X 2,574,153 11/1951 Meiners 158-116 X 2,602,497 7/1952 Buhman et a1. 158113 2,766,819 10/1956 Little 158113 2,815,070 12/1957 Lamar 158118 2,828,532 4/1958 Taylor 29157 2,867,272 1/1959 Morrison 158113 References Cited by the Applicant UNITED STATES PATENTS 2,987,119 6/ 1961 ,Alger.

FREDERICK L. MATTESON, JR., Primary Examiner, 

1. A GAS BURNER STRUCTURE COMPRISING MEANS DEFINING A CHAMBER FOR MIXING GAS AND AIR, A VENTURI TUBE HAVING ONE END OPENING INTO SAID MIXING CHAMBER, A FLAME SPREADER DISPOSED AT THE OPPOSITE END OF SAID TUBE, SAID FLAME SPREADER COMPRISING A HEMISPHERICAL BOWL HAVING, 